Pedal switch



. G. sTAUDE PEDAL Y SWITCH oct. 2, 1934.`A

Filed Nov; 22, 195o 2 Sheets-Sheet 1 E. G. STAUDE PEDAL SWITCH Oct. 2,1934.

Filed Nov. 22, 1950 2 Sheets-Sheet 2 Patented Oct. 2,1934

UNITED STATES PATENT OFFICE I PEDAL SWITCH 9 Claims.

This invention pertains to improvements in pedal operated switches,which can be used for controlling dual-powered brake mechanisms such,for example, as described in my copending d application for F'luid powercontrolling mecha.-

nism, Serial Number 375,846, led July 3, 1929 and such as described inmy copending application for Pedal switches, Serial Number 470,060,filed July 23, 1930. In both of the aforesaid apl@ plications,electrically operable means is provided for assisting brake-applyingoperation, and it is among the objects of this invention to provide aswitch winch will control the circuit to this means for assisting thebraking operation, to

.i start the motor if the pedal moves in brake- -applying direction, andto stop the motor when the pedal moves even slightly in a reversedirection, and to accomplish this result without the use of anoscillating pedal switch which is located on the pedal step as inapplication Serial No. 470,060. Although the construction disclosed inthe last mentioned application has been found practicable for theintended use, it is dimcult to apply without some modiiication of the Q5existing structure. In application, Serial No. 375,846, the circuit isnot opened to stop the motor until a maximum 'return movement ofthepedal has taken place. This is objectionable because it may happen thatthe pedal sticks, and does not fully complete its brake-releasing strokeand thus the circuit is not opened to stop the motor. In any event, themotor cannot be stopped until the pedal has completed its stroke, andthere results an unnecessary and excessive current consumpl'i tion, forexample while on a hill, or while waiting for a go" sign.

The construction described in my application, Serial No. 470,060,permits the proper opening or closing of the electric circuit, and,therefore, the

f starting or stopping of the motor, but frequently the driver does notthink oi saving current and, therefore, frequentlypermits the motor torun,

, or maintains the switch in closed position when it is unnecessary.

M It has been observed in the uid power con-= trolling mechanism ofapplication Serial No. 375,-

846, that after the fluid pressure is once set up 'against the piston,it will be maintained for a 5@ tconsiderable period, even though themotor ceases ,to operate. It is, therefore, an object herein to dprovidea switch so operable by the pedal, that ,advantage can be taken of thisperiod o f-pressure maintenance to conserve current, an opening of ,5the switch taking place in case the operator eases (Cl. 20o-59) up onthe pedal as he often unconsciously does to relieve muscular strain.

An object is to so construct the switch and so connect it in the systemthat on slight pedal depression electrical contact will be made, and sothat on continued depression this contact-will be maintained, and sothat after the pedal has been depressed to any given degree and if aslight reverse movement takes place due to less muscular action on thepart of the operator, the contact will be immediately broken, but can beagain made substantially instantly if the pedal is again pushedforwardly. This arrangement allows for what is known as inching", thecon tacts being so arranged that a retrograde or reverse motion of thepedal substantially iins mediately opens the circuit and a forward nication substantially immediately closes it, what ever the positions of thepedal, that is whateverl the position other than its initialnon-brakeapplying position, in which the vcircuit is always open. Thus,the outstanding advantage here is that the switch is always closed atany point in the brake-applying pedal stroke, regardless of the positionof the pedal, and is always open directly i that the pedalrecedes orreverses its movement even though the distance moved be one-eighth of aninch.

Features of the invention include all details of construction, as wellas the broader ideas ci means, along-with the particular application ina braking system.

It will be understood that the switch structure per se is capable ofother uses than that shown, although the switch in combination withelectrically operable means for assisting in a brakeapplying operationis also claimed.

Features and advantages of the invention willi be pointed out in thedescription of the drawings forming a part of this application, and insaid drawings Figure l is a section through an automobile floor showingthe device in elevation, in asso= ciation with an electrically operablemeans for assisting brake-applying operation;

Figure 2 is a vertical transverse section on line 2--2 showing how aportion of the device is connected to the engine, and one arrangementfor grounding the circuit;

Figure 3 is a vertical longitudinal section of the pedal switch showingits connection with the pedal and the position of the :door board withrelation to the pedal;

Figure 4 is a sectional elevation substantially similar to Figure 3,showing the pedal depressed and the contact members in closed circuitposition;

Figure 5 is a section through the brake lever on line 5-5 of Figure 4showing the means for pivotally attaching the switch to the pedal;

Figure 6 is a longitudinal section showing a modified form; and

Figure 7 is a section on line 7-7 of Figure 6.

In the drawings, 2 represents the ordinary floor board of a motor,- carthrough which the usual foot pedal extension operates. The foot pedal 3is pivoted at 4, and is connected to an electrically operable means,generally indicated at 6, adapted to assist in the brake-applyingoperation, see copending application Serial No. 375,846. The brakemechanism is not shown, but element 5 connects the mechanism 6 with thatmechanism. 7 represents the conventional type of motor having the usualcrank case ange bolts 8. Secured to the upper part of the foot pedal 3by a U-shaped clipv 10, is a shaft block 11, clamped to the pedal bylthe nuts 12 threaded on the legs of the clip.I The block 11 has an'ex-I tension 13 'on which is mounted a cap of insulating material 14.I'he cap has a threaded connection with` the end of the sleeve 15, whichsleeve is also of insulating material', preferably of the type known ashard fiber. The opposite end of the sleeve 15 has a cap 16 of conductingmaterial, in threaded engagement therewith, or detachably secured,which'cap provides a bearing 17through which the bar 18 slides. The bar18 as a' guide, projects through the sleeve and both caps, and protrudesas shown. The member 14 provides a bearing 19. A metal conductor orcontact 20, preferably of copper, is insulated from the bar 18 by asleeve 21. A binding post 22 has threaded connection with the contact 20at 23, and cable 24 connects this'binding post with binding post 25 (seeFigure 1) of the power mechanism 6.

The lower end of the rod `18 has a threaded connection with the eye 27,see Figure 2. A bolt 28 passes through the eye and has a shoulder 31which engages the' angle plate or bracket 29. A clamping nut 30 drawsthe shoulder against the angle plate, and rigidly secures the bolt inoutstanding position. 'I'he opposite member of the angle plate issecured to the engine by one of the ange bolts 8. This is a feature. Inorder to form an anti-rattling joint, a spring 32 bears against the eye,and against a washer 33 which engages the head of the bolt 34', thusforcing the eye against the angle plate but permitting a hingingmovement, and at the same time establishing a ground for the electriccircuit.

A spool-shaped contact member 35 is housed by the sleeve 15, but is notconnected thereto, and is provided with a terminal recess 36. Withinthis recess is a iiat spring 37 which bears against the spool 35 andagainst the rod 18 to establish a friction resistance, or a yieldablefriction connection. The member 35 can engage at point 38 with -contact20, when the sleeve is translated by the pedal as the pedal moves inbrake-applying direction. This is possible because members 16,35, 21 and14 slide on the lbar 13. The member 14 is pivoted at the point 13, and,therefore, the frictional resistance of the spring 37 against the shaft18 causes the contact 35 to remain stationary until contact 20 engagesit. This engagement closes the circuit to the motor. This circuit-closedposition is shown in Figure 4. Just as soon as pedal motion is reversed,even if the movement is as small as one-eighth of an inch, sleeve 15 ismoved in the opposite direction, and 20 moves away from 35 instantlyopening the circuit and'stopping the motor. Whatever the positionlofthev pedal, the slightest downward movement closes the circuit andstarts the motor, and the slightest upward movement breaks the circuitand stops the motor.

By the use of this switch and by connecting it as shown in thesystem,with the electrically operable means for assisting brake-applyingoperation, the driver can automatically maintain the pressure and holdthe car under brake control, with the motor circuit open and the motorstopped. Directly that additional power is required, he substantiallyunconsciously again presses a little harder on the pedal which instantlycloses the switch and starts the .motor until itrecovers its pressure.It will be noted that this pressure is only lost by slight seepage pastthe pump gears. Directly that the pressure is again suiciently raised,lthe driver almost unconsciously permits the pedal to retractsutilciently to again open the motor circuit. In this way asubstantialreductin in current consumption is obtained, and in practiceactually onethird of the amount of current is required, as is requiredin a system in which this present invention is not used, or in which thecontrol is notl substantially automatic in the manner above set forth. y

`It will be noted that the housing 15. is made of insulating materialand that the contact 20 is insulated from the rod and that the element20 and the cap elements 16 form stops which alternately engage theelement 35 in a manner to move it alternately in opposite directions. Itwill be further noted that there is a lost motion effect. The sleeve 15houses the entire mechanism, and the detachable arrangement of the capspermits of quick assembly.

In Figure 6 is shown a modified form of switch,

41 is made in two pieces, as best shown in Figure- 7 and is held inyieldable frictional contact with theb rod 18 by a coil spring 42 whichhas a constricting action. One of the advantages of this construction isthat when the conical surface 39 engages the conical surface 40, thereis aconstricting action on the element 41, which increases thefrictional contact between the member 41 and the bar 18; a kind ofwedging action. On reverse pedal motion, this pressure is decreased andfriction is then supplied only by thespring 42.

'I'he spring 42 may be of any conventional design that is capable ofholding the two members 41 into frictional contact with the shaft 18.lIn actual practice, the arcing of this switch is not suincient to causethe surface to become pitted to any appreciable extent, particularly ifthe area of Vcontact is sumciently great. I1' there should be somedifliculty in this' respect, the element 15a can merely be inverted andlled or partly lled with oil following the ordinary practice forovercoming such diiiiculties. The pedal switch just described may bemodified in many ways without departing from the spirit of thisinvention, since the invention consists` largely in making a switchdevice that is controlled by the direction of movement of the pedal. Inview of this, there is no intention of being entirely coni-lned to thespeciflcstructure, since that may be modiled in various ways withoutdeparting from the invention. The construction is applicable to any typeof existing pedal without drilling any openings, and the unit may,therefore, be applied to any existing automobile in a few minutes time.Aside from the value of current saving, the fact that it gives theoperator automatic control and that it is inexpensive in constructionand may be quickly applied to existing cars, is of utmost importance andof great value, especially when used with devices similar to that shownin the drawings. Instead of grounding the circuit on the motor, as shownin Figure 2, member 18 may be insulated f om the bolt 28, and thelivewire be connected to the member 18 and the power unit 6 grounded. Thisis mentioned because anyone skilled in the art could easily use othertypes of wiring diagrams.

I claim as my invention:

1. A rod, a contact sleeve having a yieldable friction and conductingconnection with the rod, a sleeve directly slidable on the rod andhousing the contact and also housing a contact insulated from the rodand adapted to engage the other contact when the sleeve is translatedand when so engaged to translate the same, said sleeve having meansadapted to entrain the friction contact in an opposite direction afterseparation of said contacts, said means comprising a cap detachablysecured to said sleeve.

2. In combination with a brake pedal of an automobile, a switchstructure having a rod pivotally supported independently of the pedal, arst contact having a yieldable frictional connection with said rod, aninsulating sleeve slidable on the rod and having a contact movabletherewith and insulated from the rod, said sleeve being pivoted to thepedal, the contacts being so related that they are in open circuitposition when the pedal is fully retracted and so related that theyassume circuit making position when the pedal is depressed and remain incontact as the pedal motion continues in the same direction, and sorelated that on reverse movement of the pedal the contacts assume andare maintained in circuit open position during continued reverse motion.

3. In combination in an automobile an engine, a brake pedal, a supportpivoted to the engine, a switch structure including contact membersmovable upon the support, and means by which the members are controlledby the pedal to be substantially instantly moved to closing positionwhen the pedal is depressed, and so that instantaneous opening orclosing of the switch takes place in correspondence to the direction ofpedal motion whatever the position of the pedal between its motionlimits.

4. In combination with an automobile a brake pedal, a supportindependently pivoted, a housing slidable on said support and pivoted tothe pedal and having therein first and secondswitch contact membersseparately slidable upon the support, the rst member being movablerelative to the -housing and the other being movable with other in adirection away from their pivotal points, first and second switchcontact members separately slidable upon the support, means pivoting oneof the switch members to the control member, and means carried by thatswitch member for entraining the second switch member when the controlmember moves in one direction, the parts being so associated thatmovement of the control member in an opposite direction closes theswitch and the elements being so related as to be substantiallyinstantly moved from one control position to another in correspondenceto motion of the control member, whatever the position of the controlmember between its motion limits.

6. In combination, a pivoted control member, a support independentlypivoted, the pivotal axes of the support and control member beingsubstantially parallel, first and second switch contact membersseparately slidable upon the support, means pivoting one of the switchmembers to the control member, and means carried by that switch memberfor entraining the second switch member when the control member moves inone direction, the parts being so associated that movement of thecontrol member in an opposite direction closes the switch, and theelements being so related as to besubstantially instantly moved from onecontrol position to another in correspondence to motion of the controlmember, whatever the position of the control member between its motionlimits.

7. In combination an automobile, a brake pedal, a rod pivoted to theautomobile forwardly of the pivotal point of the pedal, an insulatinghousing pivoted to the pedal and slidable on the rod, a. rst contactcarried by the housing out of electrical contact with the rod, a secondcontact slidable on the rod in electrical contact therewith andengageable with the rst contact, means frictionally resisting butpermitting sliding motion of said second contact on the rod, saidcontact being limited for slight reverse motions by the housing andfirst contact, and a circuit which is completable through the firstcontact, rod, and second contact.

8. A pedal, a rod pivoted independently of the pedal, an insulatinghousing pivoted to the pedal and slidable on the rod, a first contactcarried by the housing out of electrical contact with the rod, a secondcontact slidable on the rod in electrical contact therewith andengageable with the first, contact means frictionally resisting butpermitting sliding motion, said contact being limited for slight reversemotions by the housing and lirst contact, the pivotal points of thepedal, rod and housing being so related that reverse sliding motions ofthe housing on the rod are obtainable conformably to corresponding andslight pedal motions.

9. In combination with an automobile, a brake pedal, a support ofconducting material having a conducting pivotal connection with aconducting part of the automobile, an insulating element slidable on thesupport and pivoted to the pedal,

va first contact xed for motion with the insulating element, a secondcontact movable relatively to said insulating element and support and inconducting relation with said support, said contact being limited forslight reverse motions by the insulating element and the first contact,and a circuit which is completed through the contacts, conductingsupport Aand said conducting part of the automobile.

EDWIN G. STAUDE.

